1. Field of the Invention
The present invention relates generally to posts for holding up signs, signal flags, and the like. More particularly, it relates to a collapsible highway sign having an integral driver for driving said signpost into the ground.
2. Description of the Prior Art
During highway construction and repair it is often necessary to place temporary signs and signal flags by the roadway to inform motorists of road conditions ahead. Most often, the signs and signal flags are supported on a temporary signpost which is inserted into the ground and supported thereby. It has been found desirable to provide such signposts with an integral driver for driving the signposts into the ground without use of additional equipment. Such a driver is described in the patent to Matson (U.S. Pat. No. 3,381,763) wherein a stake is provided with a weighted sleeve about the shaft of the stake. Upper and lower collars are provided on the shaft of the stake so that the stake may be driven into the ground by hammering the weighted sleeve against the lower collar. The stake may be removed from the ground by hammering the weighted sleeve against the upper collar. A similar concept is disclosed in the patent to Matson (U.S. Pat. No. 3,519,234). There, the main shaft of the signpost is a hollow cylinder which receives a piston and shaft through one end. Ground-penetrating blades are mounted on the shaft at the end opposite to that of the piston. By hammering the cylindrical body against an anvil or pad mounted on top of the blades, the stake may be driven into the ground. To remove the stake, the cylinder is driven against the piston located at the upper end of the shaft to apply an upward force on the blades.
It is desirable that signposts of the type described hereinabove be sufficiently long to support the display well above ground level. It is also desirable that the signposts be sufficiently short to facilitate transportation. The prior art disclosed hereinabove includes signposts of fixed length which must compromise between the aforesaid competing desires.
It is therefore an object of the present invention to provide a signpost which may be extended to any desired elevation and which may be collapsed into a compact configuration for transportation.
It is a further object of the present invention to provide a signpost in which the various elements thereof may be firmly secured for travel with minimum preparation.